Well casing perforation cleaner



Aug. 27, 1940. a. w. McCUNE WELL CASING P ERFORATION CLEANER Filed Feb. 24, 1949 Patented Aug. 27, 1940:

UNITED. STATES PATENT OFFICE- V WELL 'casm'c PERFORATION CLEANER Burton w. Meoune, Bakersfield, Calif.

Application February 24, 1940, Serial No. 320,111

4' Claims.

This invention relates to the class of well drillthe middle portion of the same being broken ing apparatus and pertains particularly to an improved perforation cleaner.

In the operation of oil wells, the well casing in the area. from which the coil is drawn is provided with strainer perforations which function to permit the oil to pass through without allowing sand or stones to enter the casing, and these perforations frequently become filled up or clogged and have to be opened so that the desired flow of oil may be maintained.

The present invention has for its primary object to provide a cleaner for such casing perforations which will function efiiciently to remove material which has filled up the perforations, without puncturing or otherwise damaging the casing in which the perforations are formed.

Another object of the invention is to provide a-perforation cleaner in which the cleaning units forming a part of the cleaner structure are constantly maintained with firm pressure'against the inner surface of the casing to be projected as may be necessary when points of the units pass over perforations with suiiicient force. to

quickly and thoroughly remove sand, rocks or other material from the opening.

A .still further object of the invention is to provide a well casing perforation cleaner. consisting of a carrier body adapted to ,be moved up and down in the caslng,, to which are attached a plurality of resilient loops which are bowed outwardly .irom the carrier toward the casing and which support rotatable pointed units 1, in such a position that the points thereof will with the understanding, however, that the in-' vention is not to be confined to any strict coniormity with theshowing of the drawing but may be changed or modified so long as such r changes or modifications mark no material departure from the salient features of the inven+ tion as expressed in the appended claims.

In the drawing: 7 mp1 is a view in elevation of the perforation cleaner embodying the present invention,

away.

Fig. 2 is a longitudinal sectional view through a portion of the cleaner structure taken on the line {-2 of Fig. 1. 5 Fig. 3 is a transverse section taken on theline 3-3 of Fig. l. I

Fig. 4 is a transverse section taken on the line 4- 4' of Fig. 1.

Referring now more particularly to the draw- 10 ing, the numeral I generally designates the body of the perforation'cleaner structure which consists of a rod of substantial length, which is preferably of circular cross-section, as shown. Upon the upper end of this rod is a head 2 provided 15 with a threaded stem 3 by means of whicha rod line may be coupled to facilitate raising and lowering the body in the well casing. The lower end of the body mayhave a finishing oif foot piece 4 attached thereto or formed integrally 2o therewith.

Adjacent the upper and lower ends of the body there are secured in equi-distantly spaced relation thereabout, the outwardly bowed resilient guide springs 5, each of which is preferably 25 formed of a strip of resilient band-like metal having one end looped, as indicated at 6, to be a receiving recess in the wall of the body while at its other end it is straightened out to pro- 30' vide a foot piece I which is slidably engaged in. a channel 8 formed longitudinally in the body. As will be readily apparent, these four guide springs at the upper and lower ends of the body I function 'to maintain the body in the center of 35 the well casing, the springs yielding as the body is inserted to adjust themselves to the casing diameter.

Between the upper and lower groups of guide, springs, the body I is provided with longitudio nally spaced, longitudinally extending through slots 9. here shown as arranged or divided into two groups, those of one group beingall disposed in a common plane which is perpendicular toa plane common to those of all of the other groups. 45 As shown clearly in Fig. 2, the slots of one group alternate with the slots of the other group, thus providing for the novel arrangement of the perforation cleaner units about to be described.

Secured to the body I is a series of outward- 50 ly bowed spring carriers, each oiwhich is indicated generally by the numeral l0. Each of these carriers consists of a" relatively long strip of resilient band-like material which is arranged to extend longitudinally of the body and to extend longitudinally of and over a side of an opening 9. These carriers are shaped so as to have a central or intermediate portion H which is offset from a sliding foot portion I2 formed at one end and a fixed foot portion l3 formed at the opposite end and the fixed foot portions of the carriers are each secured by screws I 4, as shown in Fig. 2, within a suitable recess below the end of the slot over which the carrier lies while above the same slot, the wall of the body is provided with a guide groove l5 in which the sliding or movable foot portion of the carrier positions, the sliding foot portion being maintained in place in its guide groove by a guide band or loop l6 which is secured across it and across the groove in which it is located. Thus it will be seen that each carrier has its offset intermediate portion ll disposed over and longitudinally of one side of a slot 9 of the tool body I, and that this oiiset portion of the carrier may be moved relatively to the body under the application of pressure.

Each carrier in is provided in the ofifset central portion II with a longitudinal slot H across which extends, upon the inner side of the carrier, a

pivot pin l8 which is maintained in position by the engagement across its ends of bearing loops I 9. Each of these pivot pins carries a pointed wheel indicated generally by the numeral 20, such wheel having a series of arms 2|, each of which terminates in a point 22. Each of the wheels is formed of flat material so that the wheel may rotate in the relatively narrow adjacent slot 9. By this mounting arrangement for the pointed wheels, it will be readily seen that each point of each wheel may be brought into a position where it extends directly radially with respect to the body I on which it is carried.

In the operation of the present tool, the body is inserted into the well casing, being centered by the upper and lower groups of spring guides 5 and as it is lowered in the casing, the points of the wheels will engage the wall of the casing so that the wheel will turn and the spring carriers for the wheels will be forced inwardly so as to accommodate the wheels to the casing diameter. When the perforated area of the casing is reached, the points of the wheels as they come into line with the casing perforations, will be forced outwardly by the spring carriers through the perforation and will thus function to punch out any sand or stones which may be stuck in the opening. As the end of the perforation is reached by the end of the pointed arm, the wheel will turn and will then continue to rotate against the inner side of the casing until another perforation is reached and is in the proper position for the projection of a point of the wheel therethrough, whereupon the punching operation will be repeated for the removal of I material from the opening.

It will be noted that whereas the carrier springs are of suflicient strength to effectively punch out material which may be stuck in the perforations, they are not of such strength as to cause the points of the wheels to puncture or otherwise damage the casing walls, so that the device will not produce new perforations in the casing but will merely operate to clean out those which are already formed therein.

It will also be noted that by arranging the slots 9 in the manner stated, the cleaner wheels can be disposed around the body I substantially in a spiral path, thus insuring that as the body I is lowered in the casing, the casing wall entirely around the body will be engaged at some point by an arm of a wheel.

What is claimed is:

1. A well casing perforation cleaner, comprising an elongated body adapted to be lowered longitudinally into a well casing, a plurality of Wheel members each having a number of pointed arms, and means for supporting said wheel members on said bodythroughout the length thereof for rotation on axes extending transversely of the body between said centering means and each being normally resiliently held in spaced relation with the body, and a fiat wheel having a plurality of pointed arms rotatably supported upon each carrier for turning upon an axis ex- I tending transversely of the rod body.-

3. A well casing perforation cleaner, comprising a rod-like body, means at one end of the body facilitating the attachment of a supporting line therewith, resilient means adjacent each end of the body for centering the same longitudinally in the casing, a plurality of carriers secured to the body between said centering means and each being normally resiliently held in spaced relation with the body, a flat wheel having a plurality of pointed arms rotatably supported upon each carrier for turning upon an axis extending transversely of the rod body, and said rod body having a slot cut therein and extending longitudinally thereof beneath each carrier to receive the arms of the adjacent wheel as the latter turns.

4. A well casing perforation cleaner, comprising a rod body, means at one end of the same for coupling a suspension line thereto, said rod body having a pluralityof longitudinally spaced, longitudinally extending slots formed therein, an elongated bowed carrier extending longitudinally of and over each slot, each carrier having one end secured against movementto the body and having its other end slidably engaging thebody. each carrier having an intermediate portion which is offset from the body, the offset portion of each carrier having a longitudinal slot therein alining with the adjacent body slot, a pivot pin carried by an intermediateportion of each carrier and extending across the slot thereof, a fiat wheel having a plurality of pointed arms rotatably supported upon each pin and extending through the adjacent carrier slot, the body slot adjacent each wheel receiving the ends of the arms thereof as the wheel is rotated, and means at each end of the rod body for centering the same in a well casing.

BURTON W. MCCUNE' 

